1. Field of the Invention
The invention relates to the novel use of certain phenylglyoxylic acids and derivatives thereof in the treatment of ischemic heart disease and the hyperglycemia of diabetes. The invention also relates to a pharmaceutical composition of the useful compounds in a unit dosage form.
2. Description of the Prior Art
Ischemic heart disease is characterized by the obstruction of the major blood vessels which service the heart, resulting in decreased oxygen supply to myocardial tissue. During physical stress the reduction in the myocardial oxygen supply results in extreme cardiac pain known as angina pectoris.
Although nitrates, such as nitroglycerin, are the drugs of choice as vasodilators in the treatment of ischemic heart disease, they suffer from a short duration of action.
Diabetes, which is characterized by the elevation of blood-glucose levels, is most frequently treated today by diet, insulin injections or sulfonylurea therapy. Dieting as a means of controlling the symptoms of this disease is sometimes quite difficult and is not sufficient in cases where the diabetes is severe; insulin injections are especially useful in advanced stages of this disease or where the patient does not have an effectively functioning pancreas; and sulfonylureas are useful in the more moderately severe cases of diabetes where the patient does have a functioning pancreas. The compounds which are the subject of this use invention are effective in the treatment of ischemic heart disease and in combatting the hyperglycemia of diabetes.
The compounds of the present invention and various derivatives thereof are known in the art. German Pat. No. 949,521 discloses a substantial number of phenylglyoxylic acids as sun screening agents.
U.S. Pat. Nos. 3,532,737; 3,657,325 and 3,754,006 claim a variety of substituted alkyl esters of phenylglyoxylic acid as hypoglycemic agents useful in lowering the blood sugar levels in diabetic subjects.